The same week that Brian Williams recanted his story about being in a helicopter when it was downed by enemy fire, questions have arisen regarding claims the NBC new anchor made during interviews about his coverage of hurricane Katrina. Is he facing a tipping point?

Brian Williams speaks at the 8th Annual Stand Up For Heroes in November, presented by New York Comedy Festival and The Bob Woodruff Foundation in New York. Williams has admitted he spread a false story about being on a helicopter that came under enemy fire while he was reporting in Iraq in 2003.

The NBC anchor used to be a genial news-reader whose reporting jaunts gave him an image of tough journalistic experience. Ted Baxter was the local newsman on the old “Mary Tyler Moore Show,” whose ego, booming voice, and shallowness were played for laughs.

These two were different characters – until perhaps this week. Mr. Williams has drawn heavy criticism for exaggerating the dangers he faced in Iraq in 2003, claiming his helicopter had been hit by enemy fire when it hadn’t. Now his problems are multiplying as critics pick at more of his old stories. New Orleans journalists are questioning Williams’ gripping stories about the dangers he faced when covering the impact and aftermath of Hurricane Katrina in 2005.

Katrina reporting provided a big boost to Williams’s image (as it did for many journalists, including CNN competitor Anderson Cooper). In a 2006 interview, Williams recalled watching a dead body float past his French Quarter hotel during post-Katrina flooding and described the hotel as “gang-ridden.” He was rescued from thugs in a stairwell by a New Orleans policeman, he said in 2007.

But as the Louisiana newspaper The Advocate reports today, the French Quarter remained dry during Katrina. It is the historic high ground for the city along the Mississippi River. Nor was it gang-ridden following the storm.

The paper further questions whether Williams could have contracted dysentery from accidentally drinking floodwater, as he has claimed.

It’s possible Williams is facing a tipping point. Right now his bosses at NBC seem supportive, or at least supportive enough. They’ve accepted his on-air apology as genuine, they’re standing behind him, and he does not face disciplinary action, according to the Los Angeles Times.

But that might change if more of his tales of derring-do become suspect. To NBC’s leaders, the nightly news is a business venture more than a public trust. They can’t afford for its central figure to turn into a figure of scorn or fun, a sitcom character like Ted Baxter. That might accelerate the long-term erosion of the network news audience.

On the other hand, many of the fiercest attacks on Williams have come from fellow journalists. They think he’s impugned his own credibility and besmirched the profession. His predecessor, Tom Brokaw, wants Williams fired, according to the New York Post. Brokaw denied this report following its publication, saying that Williams's future is up to NBC News. Freelance war correspondent Michael Yon, who is also a former special forces soldier, tweeted, "Brian Williams Must Resign -- if Mr. Williams does not resign or get fired, I will not link again to NBC."

The general public may not care so much. They already have a low opinion of journalists, who routinely rate below used-car salesmen and politicians in terms of public approval. And they’re not so sure that the media are credible, anyway. A 2012 Pew Research poll found that 56 percent of respondents gave the media a positive believability rating, and 44 percent gave it a negative one.

From 2002 to 2012, the believability of a broad range of news sources suffered “broad-based declines,” according to Pew.

And the anchors of the network evening news just aren’t as important to the culture as they used to be, or as famous. In 1985, about half of respondents to a Pew survey could identify then-CBS news anchor Dan Rather from a photo.

In a similar 2013 survey, when shown a picture of Brian Williams, only 27 percent of respondents knew his name.